Webneb schtjlemann



Patented eb. 26, 1929.

UNITED STATES PATENT OFFICE,

WERNER scnULEm-Nn, or vonwmxnn-on-rrrn-nnmn, AND rnrrz scnomrornn AND FRITZ MIETZSGH, F ELBERFELD-ON-THE-RHINE, GERMANY, ASSIGNORS TO WINTHROP CHEMICAL COMPANY, INC.,

0 1 NEW YORK, N. Y.

NEW 6A1'.|KOXY-S-ALNLINOrQUIILNOLINIIJS.

No Drawing.- Application filed January 30,3926,

The present invention concerns the manufacture of the hitherto unknown 6-alkoxy-8- amino-quinolines,which likewise exhibit antipyretic properties similar to those of the 5-amino-8-ethoxy-quinoline, and also exert a strong specific destroying action on blood parasites.

These compounds are obtained by the reduction of t6-alkoxy-S-nitro-quinolines or from 6-alkoxy-8-azoaryl-quinolines according to the methods ordinarily used for the reduction of these compounds. The manufacture of the new compounds can also be carried out by the alkylation of the oxygen of the hydroxyl group of primary bodies such for example as 6-hydroxy-8-formyl-aminoquinoline or 6-hydroxy-8-benzalaminoquinoline with subsequent splitting off of the formyl or benzal groups or by direct alkylation of 6-hydroxy-8-amino-quinoline.

The 6-alkoxy-8-amino-quinolines are intended to find application as curative products and to serve as intermediates for the manufacture of derivatives Wl'llCh are of value in pharmacy.

The following examples will serve to illustrate our invention, it being understood that the proportions given and the mode of working may be Varied without deviating from our invention. The new products are generally whitish crystalline products forming soluble salts with hydrochloric acid.

Ewample- 1.

The following example illustrates one method of preparing 6 -methoxy-8-aminoquinoline having most probably the following formula:

5 (6) GHaO 3 N 1 (8) NH:

Serial H 0. 85,080, and in Germany April 29, 1925.

coolingthe stannous chloride double salt separates {this is filtered ofi', washed with hydro-' chloric acid of 30% and decomposed inthe customary manner.

The resulting 6-methoxy-8-amino-quinoline distils at 137-138 C. at a pressure of about 1 mm; of mercury. It forms a viscous, light yellow oil, which solidifies to an almost white crystalline mass, having a melting point of 41 C. With hydrochloric acid it forms a beautifully crystalline dihydrochloride, possessing an orange'colour and which dissolves in cold water with difliculty. Instead of stannous chloride other reducing agents can be used, such as zinc or iron, or electrolytic reduction may also be resorted to, etc.

Example 2.

The following example illustrates one method for preparing '6-ethoxy-8-aminoquinoline haying most probably the following formula:

lution of 30% and finally with water. After distilling ofl the ether, the residue is subjected to hydrolysis by dissolving in 3 litres of dilute sulphuric acid of about 20% strength and heating under reflux action for about 46 hours The solution is neutralized with sodium carbonate, extracted with ether, the etheral solution is washed thoroughly with caustic soda solution of 30% and with water and thereupon dried over anhydrous potassium carbonate, after which the ether is distilled oil. The 6-ethoxy-8-amino-quinoline thus produced distils at E l-145 C. at a pressure of about 1 mm. The yellow, oily distillate solidifies comparatively quickly to a coarse crystalline amino-quinolines having most probably the mass of a meltin point of 60 C. The dihydrochloride exhi its very similar properties with regard to colour and solubility to those of the lower homologue described in Example 1.

We claim:

l. The herein described new 6-alkoxy-8- following formula:

R standing for an alkyl group, which are generally whitish crystalline powders forming soluble salts with hydrochloric acid, exhibiting antipyretic properties and exerting a strong specific destroying action' on blood parasites.

2. A process for the manufacture of 6- alkoxy-S-amino-quinolines from compounds having most probably the following formula which comprises alkylating the hydroxyl radical.

3. A process for the manufacture of 6-alkoxy-8-aminoquinoline compounds which comprises subjecting a. compound of the general formula I wherein NX represents an amino group of being a crystalline material melting at about 60 G., forming soluble salts with hydrochloric acid and exhibiting antipyretic properties. In testimony whereof we have hereunto set our hands.

WERNER SQHULEMANN.

FRITZ SGHONI-IFER. FRITZ MIETZSCH; 

